It can be done, I put a Vortech crate in a 76 'Vette. There's a little more to it than just the intake, which is just a conversion intake but specific to the Vortech heads. I think you will also need a waterpump and a flex plate/flywheel to adapt to the older drivetrain parts too, and maybe a new balancer. I would go talk to a GM parts guy, he'll have a list of parts and instuctions as to adapting a Vortech to your truck,
Scott